Pneumatic hammer.



F. M. FABER.-

PNEUMATIC HAMMER.

APPLICAT'ION FILED SEPT. 2. 1913.

1 1 84.33 1 Patented May 30, 1916.

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N ITWESSES. CQJM ll TTOHNEY F M. FABER.

PNEUMATIC HAMMER.

APPLICATION FILED SEPT. 234913] Patented May 30, 1916.

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.4 -0HIVEY F. M. FABER.

PNEUMATIC HAMMER I APPLICATION FILED SEPT. 2. 1913.

Patented May 30, 1916.

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TTTEU erarne PATENT UFFT@F..

FRANK M. FABEB, OF CANTON, OHIO.

PNEUMATIC HAIWIMER.

Application filed September 2, 1913.

To all whom it may concern:

Be it known that I, FRANK M. FABER, a

citizen of the United States, residing at Canby the position of the piston in the cylinder when compressed air or other fluid under pressure is admitted into the hammer; and the objects of the improvement are to provide a, valve block forming part of the cylinder, with a cylindric valve around the block, so that the piston can slide in and through the block without impinging the block or coming in contact with the valve; and to provide large admission and exhaust ports for increasing the rapidity of the strokes and the force of the blows; the special purpose of the invention being to embody these improvements so as to make the complete hammer of minimum size and weight.

The objects and purposes of the invention thus set forth. in general terms are attained by the preferred embodiment thereof illustrated in the accompanying drawings, forming part thereof, in which-- Figure 1 is a vertical longitudinal section of the improved pneumatic hammer; Fig. 2, a similar section of the valve block and surrounding parts showing the valve in its rearward position; Fig. 3, a similar section of the valve block and the valve showing the valve in its forward position; Fig. 4C, a forward end view of the valve block and valve detached from the cylinder; Fig. 5, a cross section of the valve block and valve on line 55, Fig. 8; Fig. 6, a cross section of the valve block and valve on line 6-6 Fig. 3; Fig. 7, a cross section of the valve block and valve on line 7-7, Fig. 3; Fig. 8, a cross section of the valve block and valve on line 8 S, Fig. 3; Fig. 9, a cross section of the valve block and valve on line 99, Fig. 3; Fig. 10, a cross section of the valve block and valve on line 10-10, Fig. 3; Fig. 11, a cross section of the valve block and valve on line ll ll, Fig. 3; and Fig. 12, a rear end Specification of Letters Patent.

Patented May 3U, 19%.

Serial No. 787,558.

view of the valve block and valve detached from the cylinder and the valve cap.

Similar numerals refer to similar parts throughout the drawings.

The handle 1 is provided with the tubular body portion 2 which is secured to the rear end of the cylinder proper 3 by the screw threads 4 and a suitable locking device 5, so that the body portion of the handle forms a rearward extension of the cylinder proper with an interior diameter corresponding generally to the exterior diameter of the cylinder proper, and the transverse portion 6 of the handle forms the rear head of the cylinder, in which is provided the annular admission port 7. 7

The valve block 8 is cylindric in general form and has its forward end 9 neatly fitted to the rear end 10 of the cylinder proper, as by being counter-sunk therein; and is provided on its rear end with the valve ring 11, the rear face of which is neatly fitted to the inner face of the rear cylinder head 6, the valve block and the valve ring being tightly clamped between the cylinder proper and the handle-head thereof by the screw connection of the handle with the cylinder.

The valve 12 is cylindric in general form and is located around the valve block and valve ring between the rear end 10 of the cylinder proper and the flange 13 of the valve ring 11, the parts being so proportioned that the annular exhaust chamber 14 is formed around the valve inside the tubular portion of the handle. In the construction shown, the valve block is secured against rotation with reference to the cylinder proper, and the valve ring is secured against rotation with reference to the valve block, by means of the dowel pins 15, so that the various ports will register with each other.

It will be understood that the inner diameter of the valve block and the valve ring are the same as the inner diameter of the cylinder proper, so that these parts form the rear portion of the cylinder and that while these parts are shown and described as separate pieces, and are preferably so made as a convenience in construction, it is not essential that they should be so made.

The valve ring and the rear portion of the valve block are provided with a series of longitudinal admission ports 16 and 16", all of which communicate with the annular admission port 7, and extend forwardto and beyond the annular series of radial transmission ports 17 opening outward from the valve block, as shown in Fig. 10; and a portion at least of the longitudinal admission ports 16 extend forward to and communicate 1 with the radial pressure ports 18, also opening outward from the valve block, as shown 7 in Fig. 8.

The'forward portion of the valve block and the wall of the cylinder proper are provided with the series of transmission ports '19, extending from the series of radial feed ports 20 opening inward from the periphery of the valve block, as shown in Fig. 9, forward to the series of radial transmission i der proper is provided with at least one actuating port 23, which opens at 23 from an intermediate portion of the cylinder; de-

' spending upon the desired length. of. the

stroke, and extends thence rearward and opens youtward "at the external annular shoulder 24'for'med on the valve block.

The rear portion of the valve block is also providedwith the series of radial admission ports 25, the same extending inward from the periphery of the valve block to the Q10 interior thereof andbeing located, inpart at least, in rear of the adjacent series of radial admission ports 17 as shown in Fig. 11. And the forward portion of the valve block is provided with the series of radial exhaust ports 26, the same extending outward from the interior of the valve block to'the annular exhaust groove 26 formed in the periphery thereof, as shown in Figs. 3 and'5. t

The valve 12 is provided with the intermediate annularshoulder 27 corresponding to the external annular. shoulder 24; on the valveblock and adapted to abut the same for stoppingthe valve at the end of its forward stroke, as shown in Fig. 3.. The internal diameter of the valve in front of this shoulder is uniform and makes a neat 'slidingfit with the periphery of the ribs 28, 2-9 and 30 at the sides of the grooves 6, 26. and 22?, which ribs form the periphery of this portion of" the valve block. The rear end ofthe valve is counter-bored to form the deep rabbet 31, in front of which is'provided the annular internal transmis- "6 5i sion groove 32 in the valve; and the internal diameter of the ribs 33 and 34; on the sides of this groove is uniform, and has a neat sliding fit with the periphery of the rear portion of the valve block upon which they slide.

' The internal diameter of a certain portion of the valve is made slightly larger than the adjacent portion in rear thereof, to form an annular shoulder in the valve for receiving a constant pressure of the actuating fluid for holding or steadying the valve in its rearward position. In the present embodiment of the invention this portion of the valve is the intermediate portion 35 between the shoulder 27 and the rib 33, thus forming the shoulder 36 on the forward side of this rib; the shoulder 36 being located opposite the opening of the radial pressure ports 18 when the valve is in its forward position, and the slightly enlarged diameter of the intermediate portion 35 of the valve as compared with the external diameter of the valve block in rear of the radial pressure ports 18 permits the pressure of the actuating fluid admitted through the longitu dinal ports 16 and the radial ports 18 to be constantly exerted against this shoulder.

The rear end portion 37 of the valve overlaps and has a neat sliding fit with the periphery of the valve ring 11, and the end of the valve is adapted to abut and be stopped by the flange 13 on said ring when the valve is in its rearmost position. The rabbeted portion of the rear end of the valve in conjunction with the rear end 38 of the valve ring thus forms the annular admission channel 39 communicating with the radial admission ports 17 and 25 when the valve is in its forward position, as shown in Fig. 3; and the parts are so proportioned that when the valve is stopped by theimpingement of its rear end 40 against the flange 13 of the valve ring, the rear portion of the rib 34 is in rear ofthe radial ports 17, but does not contact with the forward end of the valve ring, thereby maintaining the annular channel39 in constant communication with the radial ports 25 as shown in Fig. 2.

The parts are so proportioned that the annular shoulder 34 formed on the rear side of the rib 34: is greater in area than the annular shoulder 36 formed on the forward side of the rib 33, but less than the combined areas of the shoulder 36 and the shoulder 24 on the valve. The valve is furthermore provided with the series of radial exhaust ports 41 communicating with the groove 22. when the valve is in its forward position; and with one or more leakage ports 42 leading outward from the annular shoulder 27 on the valve.

A suitable tool 43 for cutting, drilling or riveting is slidingly mounted in the forward end of the cylinder; and the piston 44 is shaped to freely fit and slide dwise in and through the cylinder proper, the valve block and the ring, from the rear head 6 of the cylinder to the tool 43 in the forward end of the cylinder, which tool is impinged by the piston in its forward stroke.

The handle is provided with the admis sion channels 45 and 45 the former of which communicates with the annular admission port 7, and the latter of which communicates with the inlet socket 46 which is adapted to receive a suitable hose connection for supplying air or other fluid under compression in the usual manner. Communication between the inlet channels 45 and 45 is controlled by the valve 47, which in turn is manipulated by the usual thumb lever 48. And finally, at least one exhaust port 49 is provided in the tubular portion of the handle leading outward from the exhaust chamber 14; and one or more leakage ports 50 are provided, preferably in the valve ring, to admit a small amount of air from the admission ports into this end of the cylinder.

The longitudinal admission ports 16, 16 and the radial admission ports 17 admit fluid pressure into the annular admission channel 39, and into the rear end of the cylinder through the radial admission ports 25; whence the pressure passes through the opening 23 and the longitudinal actuating port 23 against the shoulder 27 of the valve, thereby throwing the valve from its forward position, as shown in Fig. 3, to its rearward position shown in Fig. 2; in which rearward position the valve is steadied and held by the constant pressure passing from the longitudinal admission ports 16 through the radial pressure ports 18 and against the shoulder 36 on the forward side of the rib 33.

The pressure passes from the longitudinal admission ports 16, 16 to the radial transmission ports 17 into the annular groove 32 in the valve; whence the pressure passes through the radial feed ports 20, the longitudinal transmission ports 19 and the radial transmission ports 21 into the forward end of the cylinder, thereby throwing the piston toward the rear end thereof. v At the same time the rib 34 of the valve has closed communication between the radial admission port 17 and the annular channel 39, so that no pressure is admitted into the rear end of the cylinder through the radial admission ports; and the air in the rear end of the cylinder is exhausted through the radial exhaust ports 26 and the annular channel 26 past the forward end of the valve into the exhaust chamber 14 and thence out through the radial exhaust port 39.

When the rear end of the piston has passed and closed the radial exhaust ports 26, the compression of the air in the rear end of the cylinder together with the pres 1 sure admitted through the leakage port 50,

operating outward through these radial admission ports 25 into the annular channel 39 against the shoulder 34 on the rear side of the rib and by overcoming the constant reverse pressure against the relatively smaller shoulder 33, throws the valve to its forward position, thereby admitting air through the admission port 17, the annular channel 39 and the admission port 25, into the rear end of the cylinder, and driving the piston forward in its working stroke to impinge the tool 43; at the same time the air in front of the piston is exhausted through the transmission ports 21, 19 and the exhaust ports 22, the exhaust groove 22 and the series of exhaust ports 31 in the valve, to the exhaust chamber 14 and out through the exhaust port 49; whereupon the parts are in the position first assumed and the cycle is repeated.

When the parts are so proportioned that the forward end of the piston will pass to the rear of the opening 23 of the actuating port 23, before the valve is thrown forward, the quantity of air transmitted through the transmission ports 19 and 21 into the forward end of the cylinder is so limited because of the small area of feed ports 20, that the pressure fails to follow the piston in its rearward stroke, and though passing through this actuating port is not sufiicient, when acting against the shoulder 24 of the valve, to prevent the same being thrown forward by greater pressure exerted against the shoulder 34 thereof, due to the compression of the air in the rear end of the cylinder and the live leakage entering therein through the port 50. And finally, the parts are so proportioned that in the rearward movement of the valve the radial admission ports 37 are closed by the rib 34 of the valve just before the exhaust groove 26 is open, as shown in Fig. 1; thus giving the valve a slight lap to stop the admission of air before the exhaust ports are open; and the presence of the leakage ports 44 at the shoulder 27 of the valve prevents any pressure which may leak through the adjacent portions of the valve from acting upon the valve shoulder 27 and preventing a proper operation thereof. It will be understood that the leakage'ports 44 are relatively smaller in area than the actuating ports 23, so that the leakage therefrom does not relieve the pressure in the actuating port enough to permit its proper action in throwing the valve rearward.

I claim:

1. In a valve mechanism for controlling the movements of a piston in a cylinder, a valve block and a valve ring forming part of the cylinder, a cylindric valve around the block and ring, an annular channel between the block and the valve, longitudinal admission ports in the walls of the block, ad

7 mission ports in the block leading from said longitudinal ports to said annular channel, and admission ports leading from said channel into the cylinder.

2. In a, valve mechanism for controlling in the Walls of the block, radial ports'in the block leading outward from the longitudinal ports, and admission ports leading from the radial ports into'the Cylinder.

3. In a valve mechanism for controlling the movements of a piston in a cylinder, :1 cylindric block, a cylindric valve coordinated With the block, an annular actuating shoulder on the valve, one or more actuating ports in the block opening against said shoulder, and one or more leakage ports in the valve opening from said shoulder.

FRANK M. FABER.

Witnesses ELFRIEDE SCHMIDT, LOUISE M. CoRBY.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

- Washington, D. C. 

